Can anybody on this list answer the following question: My code contains a call to wait_event_interruptible_exclusive(). This results in the current task going to sleep on a wait queue. It builds a wait_queue_t struct in its current stack frame, setting the .func member to autoremove_wake_function(), adds it to the wait queue, and finally reschedules.
At a later point in time, another thread calls wake_up_interruptible() on the wait queue. This results in a call to autoremove_wake_function(), which in turn calls default_wake_function(), which then calls try_to_wake_up(). At this point, the previously sleeping task becomes runnable again. Then, after default_wake_function() returns, list_del_init() is called to remove the wait_queue_t from the wait queue. Now, since the wait_queue_t is allocated in the stack frame of the just woken-up task, which could already be running at this point, how can I be sure that the wait_queue_t is still valid at the point list_del_init() is called to remove it from the wait queue? It seems to me that I cannot and hence autoremove_wake_function() is broken, or am I missing something? Any responders pls. cc me; I am not subscribed to this list. thanks, Thomas -- -------------------------------------------------- Thomas Koeller, Software Development Basler Vision Technologies thomas dot koeller at baslerweb dot com http://www.baslerweb.com ============================== - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
